Sinn Féin President Gerry Adams has described the former Conservative Party chairman's comments, made in the wake of Mr McGuinness's attendance at a Royal banquet, as advocating assassination.Lord Tebbit, who was injured alongside his wife in the 1984 Brighton bombing, expressed contempt over the former IRA commander's historic visit to the Queen's residence at Windsor."There's always the possibility that a member of the Real IRA will be so outraged by Mr McGuinness bowing to the Queen that they might shoot him in the back for it," he said."We can but hope."Norman Tebbit and his family have been very badly hurt by the conflict - I absolutely understand that.Deputy First Minister Martin McGuinnessMr McGuinness was a guest of the Queen at a banquet to mark the first ever official visit by an Irish head of state - something he insisted did not diminish his position as an Irish republican."I went to Windsor Castle last night as an unapologetic Irish republican and I'm still an unapologetic Irish republican this morning, so I think it is possible to do these things," he told RTÉ radio."Particularly in the context of a very clear indicator that others - such as Queen Elizabeth in her visit to our country, both to Belfast and to the south - were prepared to show impressive leadership in the context of conflict resolution and acts of reconciliation."Speaking about the comments made by Lord Tebbit, Mr McGuinness added: "Obviously the sentiments that he has expressed, I think, are not fitting for someone in the elected position he has been in for a very long time."I'm not going to make an issue of it. Other people have certainly raised it with me, and some people have advocated that I should make an issue of it - I don't intend to do so."Gerry Adams added: "I fully understand that Norman Tebbitt has himself been a victim of the political conflict and I regret that he has suffered grievously."However, to publicly advocate the assassination of deputy First Minister Martin McGuinness is a shocking throwback to a violent past from which we are seeking to move on."The State visit is another important milestone in doing that."He further called for political leaders on both sides of the Irish Sea to reject the sentiments expressed by Lord Tebbit.My visit to Ireland and your visit this week, Mr President, show that we are walking together towards a brighter, more settled future. We will remember our past, but we shall no longer allow our past to ensnare our future.The QueenMartin McGuinness stood and joined in a toast to the Queen and Irish President Michael D Higgins at Tuesday night's event, as the orchestra played God Save The Queen."I believe I have the overwhelming support of the people of Ireland for what I did last night," the deputy First Minister said.However, a small protest had been held outside Windsor Castle and relatives of victims of the 1974 Birmingham pub bombings called for Mr McGuinness to be arrested."I understand that people are hurting as a result of the fall-out from the conflict," he said."Many in my community - in the republican, nationalist community - are also hurting as a result of the conflict. Different sections of that community come to this at different speeds."Mr McGuinness has now met the Queen twice, having first shaken hands during a Royal visit to Northern Ireland in 2012.